* {
    box-sizing: border-box;
}

/* body 样式 */
body {
    font-family: Arial;
    margin: 0;
}

/* 标题 */
.header {
    padding: 80px;
    text-align: center;
    background: #6cb6e8;
    color: white;
    animation: headerColor 6s ease-in-out infinite;
}

/* 标题字体加大 */
.header h1 {
    font-size: 40px;
}

@keyframes headerColor {
    0%   {background-color: #6cb6e8;}
    25%  {background-color: rgba(88, 164, 182, 0.85);}
    50%  {background-color: rgba(106, 191, 127 , 0.81);}
    75%  {background-color: rgba(97, 162, 206, 0.91);}
    100% {background-color: #6cb6e8;}
}

.loader {
    position: relative;
}

.loader span {
    position: relative;
    font-size: 2.8em;
    color: #fff;
    display: inline-block;
    text-transform: uppercase;
    animation: animate 2s ease-in-out infinite;
    animation-delay: calc(0.1s * var(--i));
    animation-play-state: paused;
}

.loader:hover span {
    animation-play-state: running;
}

@keyframes animate {
    0%,
    40%,
    100% {
        transform: translate(0);
    }

    20% {
        transform: translate(-20px) rotate3d(1, 0, 1, 10deg);
    }
}

/* 导航 */
.navbar {
    overflow: hidden;
    background-color: #494c4e;
}

/* 导航栏样式 */
.navbar a {
    float: left;
    display: block;
    color: white;
    text-align: center;
    padding: 14px 20px;
    text-decoration: none;
}

/* 右侧链接*/
.navbar a.right {
    float: right;
}

/* 鼠标移动到链接的颜色 */
.navbar a:hover {
    color: #6cb6e8;
}

/* 列容器 */
.row {
    display: -ms-flexbox; /* IE10 */
    display: flex;
    -ms-flex-wrap: wrap; /* IE10 */
    flex-wrap: wrap;
}

/* 创建两个列 */
/* 边栏 */
.side {
    -ms-flex: 30%; /* IE10 */
    flex: 30%;
    background-color: #f1f1f1;
    padding: 20px;
}

/* 主要的内容区域 */
.main {
    -ms-flex: 70%; /* IE10 */
    flex: 70%;
    background-color: white;
    padding: 20px;
    /*height: 500px;*/
    /*overflow-y: scroll;*/
}

/* 测试图片 */
.menuCard {
    color: #6cb6e8;
    background-color: #fff;
    width: 100%;
    align-items: center;
    padding: 20px;
    border-radius: 8px;
    display: flex;
    flex-direction: row;
    justify-content: space-evenly;
}
.menuCard:hover {
    background-color: #e1e1e1a6;
    width: 100%;
    padding: 20px;
}

/* 底部 */
.footer {
    padding: 20px;
    text-align: center;
    background: #ddd;
}

/* 响应式布局 - 在屏幕设备宽度尺寸小于 700px 时, 让两栏上下堆叠显示 */
@media screen and (max-width: 700px) {
    .row {
        flex-direction: column;
    }
}

/* 响应式布局 - 在屏幕设备宽度尺寸小于 400px 时, 让导航栏目上下堆叠显示 */
@media screen and (max-width: 400px) {
    .navbar a {
        float: none;
        width: 100%;
    }
}

/* 响应式布局 - 在屏幕设备宽度尺寸小于 400px 时, 让卡片上下堆叠显示 */
@media screen and (max-width: 400px) {
    .cardFlex{
        flex-direction: column;
    }
    .card{
        width: 100%;
        padding-bottom: 5%;
    }
}

/* 响应式布局 - 在屏幕设备宽度尺寸大于 400px 时, 让卡片上下堆叠显示 */
@media screen and (min-width: 400px) {
    .cardFlex{
        flex-direction: row;
    }
    .card{
        width: 32%;
        padding-bottom: 5%;
    }
}

.cardFlex{
    display: flex;
    justify-content: space-between;
    align-content: flex-start;
    flex-wrap: wrap;
}

.card{
    color: #686868;
    padding: 15px;
    margin-top: 2%;
    border: 1px solid #bebebe;
    border-radius: 8px;
    box-shadow: 0 1px 1px 0 rgba(0, 0, 0, .15)
}

.card:hover{
    color: #6cb6e8;
    border: 0px solid #6cb6e8;
    box-shadow: 0 0 8px #6cb6e8;
    transition: all .2s ease-in-out;
}

.upBtn{
    border: 1px solid #6cb6e8;
    position: absolute;
    border-radius: 20px;
    right: 65px;
    margin-top: -110px;
    color: #6cb6e8;
    background-color: #f0f8ffd4;
    font-size: xxx-large !important;
}

.upBtn:hover{
    background-color: #e1e1e1a6;
}
